Generally, axial deformation or misalignment that occurs in a turbine rotor causes imbalance of the turbine rotor, which may cause shaft vibration during operation. Excessive shaft vibration causes an abnormality in a bearing part and prevents normal operation. A further progress of the excessive vibration may lead to a break of the shaft. Thus, to prevent such a break, it is important to keep axial deformation or alignment of the turbine rotor within an acceptable value.
Turbine rotors covered by the present invention include a gas turbine rotor and also a steam turbine rotor.